Remove
the heads and arms from both figures using the boil and pop method.
Once
the head and arms are removed from both figures, "pop" apart the
bodies. To make an 'easy' version of a Borg-Cardassian, simply put the
Cardassian head on the Borg body. You'll need to add some 'hoses' or
wires
to the Ferengi head, and attach them to various parts of the body. To
'mix it up' a bit, take parts from other Borg figures such as Locutus,
and Hugh. Seriously, this is an easy custom to make, and it shouldn't
take you that long - unless you get REALLY creative and add a working
light in his eye!

PAINTING:

Black
is a 'must' for any Borg custom - but you don't need to stop there. Add
some silver, gray, or gold. You'll need to make your Borg your
own! Paint the head white, or 'off white' before attaching it to the
Borg body. be careful around the eyes and mouth. To add some
'detailing' to the face, wait for it to completely dry. Then, get your
hands dirty - literally! Add a dab of black paint (or gray) to your
finger - wipe it off on a paper towel so there's hardly any left on
your finger. When the head is dry, run the 'painted figure' over his
nose, in his ears, etc. I've found that this brings out some features
better.